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Fix a Rusty Fuel Tank

Turn off the tank fuel petcock and remove the tank from the motorcycle. I Found some tubing in the junk drawer to drain it into a container. I put a coffee filter down in a funnel first (I wanted to make sure to capture the particles so that I could feel like this trouble would all be worth the pain).

Step 1: Wax the Tank

Take a moment and wax the surface of the tank especially near the gas cap and near the petcock valve (double coat). The chemicals and sticky tape stuff will come off easier. and it will help protect if something splashes onto the paint. The fuel and chemicals are really pretty tame but it definitely will help if you do this step

Step 2: After Draining Take a Look...

I took a couple of pictures to show. It didn't seem Terrible but still pretty bad for anything that could get past the fuel filter and into the tiny jets of the carburetors. We did experience some engine cut outs when the fuel tank got pretty low on fuel. There was some on the screens of the the petcock valve as you can see.

Step 3: Next Rinse With Water

So I took a small trash can and covered it with an old t-shirt. I had a yard trash Bungee type band I got from a christmas stocking that did the trick. With the tank cap off and the petcock valve removed, I simply rinsed with the water hose capturing the remnant gas and particles into the trash can filter. Now that is quite a large amount of rust particles! I found a deserving fire ant mound to pour the gas/water slurry over and some weeds took a beating (Why waste it) . This is where I should probably mention that the directions did not suggest what to do with the chemicals and gasoline slurry which are a by-product of using the kit.. You will have to decide for yourself and let your conscience be a guide (Jiminy Cricket comes to mind...)

I did a couple of capture rinses into the trash can.

Then I rinsed several more times to be very sure any loose particles were out of the tank. Take your time and rinse until you are sure. The next two steps will also be rinse steps so if there is a little it will not matter.

Step 4: Seal the Holes

I used Gorilla tape to seal the openings. Start with the petcock hole. Dry the petcock area to be sealed up so that the tape will stick. One layer with 1" overlap did the trick for me. Really rub around the openings to seal well. The petcock hole was easier since much of the surface is flat near the opening. Make sure to cover the petcock screw holes also since they penetrate the tank and can be a leak point. Pour the marine clean and hot water per the directions into the gas cap hole (I assume you are outside for these sloshing steps). Next dry the area around the gas cap hole and apply the tape seal. I showed how I applied the tape on my gas cap hole in the picture. Really press the tape in around the rim to seal. If it leaks a little don't worry just wipe it off the painted surface. you will get one more chance to practice before the important tank seal step where it really needs to be sealed. These early steps will also begin to give you a feel for how the tank cavity is built. You will need to be an expert at "feeling" where the liquid is in the tank.... where the cavities are how it will slosh from one large cavity (on the left) to the other large cavity (on the right). At this point Stop and watch the movie Caddy Shack if you have not yet seen it (it's a classic). The scene of importance is when Ty Webb (Chevy Chase) is telling Danny Noonan (Michael O' Keefe) to "Be the ball Danny". You need to "be the liquid" . The stuff is going to be swished around with no way to determine if you did a good job. All you can see is like 1% of the inside surface. Swish it vigorously for a duration described in the directions. My arms hurt after this was all done.

As DEVO says:

Now Swish it Into shape

Shape it up

Get straight

Go forward

Move ahead

Try to detect it It's not too late

To Swish it Into shape Swish it good

Step 5: Pour in the Metal Ready

I pulled off both tape covers and drained the marine clean . I captured the first rinse in a trash can so that I could dispose of properly. The rest I rinsed out onto the drive -- it did not seem to stain. My son who is taking chemistry felt that the ingredients were pretty benign. I guess you could look up the MSDS details.

Rinse well then pretty much repeat the steps again but using the metal ready liquid from the Kit.

If you had leaks from the last step try to challenge yourself to make this step leak free (the final step really should not leak !). When you finish this swish and rinse step then the tank needs to be dry dry dry ! see the next step for my method...

Step 6: Dry the Interior

After the Marine-clean and Metal ready swish/rinses are done then it is time to dry the tank. really shake it in all angles to get any large pockets of water out. By now you are becoming an expert at figuring out where the water is (without being able to see it). Yes this picture is of a hair drier set on low and angled a little to be directed into the tank (rather than towards a tank wall). I sealed the dryer to the gas cap opening with tape allowing the air to escape from the petcock hole. I left this on for 2 - 4 hours to finish out the day. I came back periodically to make sure the dryer was not overheating and to re-situate it to avoid blowing into the same spot on the tank. I also turned it off for a few minutes every 30 minutes to let everything cool off. After 4 hours of warm air flow through the tank it was bone dry. Don't sell this step short --IT NEEDS TO BE DRY or you will have wasted all of your effort !

Step 7: Now for the Tank Sealer

Now the tank is real dry inside right?

OK re-tape the petcock hole shut (this is the last time). Shake the sealer can well, then open the can. I had a real hard time getting it open. Be very careful as it seemed like the contents had sealed the lid some making it VERY hard to get open. I made a paint stirrer using some of the gorilla tape and a long screw bit for my cordless drill. I gave it a fairly long stir until the contents were very well mixed. This is where the magic happens so take the time to make sure it is well mixed. I also took a latex glove and taped it over the can opening leaving the "birdie" finger extended (all others taped back) then I cut the finger tip off . I used it to make sure all of the magic liquid made it into the tank and not on my tank exterior paint. I also taped a cloth down around the opening incase some got loose. Pour it all into the gas tank hole then wipe the area where tape cover will stick and reseal the gas tank hole with the gorilla tape (last time).Do your very best on this seal or the magic stuff will get out on you and your tank --very bad.

Step 8: Swish the Tank Sealer

I swished for the entire time limit described in the directions (2 hours). After I was sure it would not leak I brought the tank inside to watch TV while I rotated it in all directions coating every inch of the interior. Remember "be the liquid" . Coat every where on the inside. It has the viscosity of spray paint so it drips easily but as the tank gets coated the liquid quantity becomes less. This process was more of a slow methodical rotation careful to coat both cavities including top, bottom,sides ---everywhere ! take your time on this step !

Step 9: Drain the Sealer

This part was not easy... I removed the tape covers and used the petcock hole as the leak out point. I cut a yard trash bag to make a disposable tarp on a folding table. then carefully let the stuff drip out onto the plastic bag. I was able to support my elbows on the table while I twisted the tank to drip out the contents. You want to get all of the excess out as a puddle inside could break down or not cure properly and interact with the fuel--bad thing.

So I did this until my arms hurt. the second picture is the puddle I dripped out after I thought I was done. Notice the q-tip for a size reference. When you think you are done dribbling it out go one more time to make sure.

Wipe up anything that got on the tank and then roll up the trash bag tarp and throw it away.

Step 10: Let the Tank Dry

Use a q-tip to clean the petcock screw holes . I leaned the tank at an angle and upside down. I figured that if there was a puddle it would be at the top of the tank where the fuel is seldomly sitting. The instructions say to let it dry for 4 days. I let it dry for 7 days. I also had a small electric pump we used to pump up pool rafts. I taped the pointy nozzle into the petcock hole and let it run (pushing a light stream of air through the tank) I put the pump on for 2 hour cycles off and on during the 7 day dry time. After a while the smell of curing paint went away which signaled that the tank was finally dry.

Step 11: Here Is How It Looked

I could not see inside the tank but here are some pictures through the gas cap hole ---much better.

I had to use some Goo off to remove tape adhesive from the outside of the tank. --not sure this is the best stuff to use on a painted surface but the extra wax job seemed to help avoid damage while I removed the tape gook.

As of today I put everything back together with a new fuel filter. It worked great but only time will tell if this stuff peels off or does the trick.

Hope you enjoyed the instructable and my goofy sense of humor...

Step 12: Update 1.75 Years Later

Stop now if you are tired of my stories...So I continued to have issues with the fuel system after the tank resurface kit. I took the cycle to two different mechanics for repair work and truthfully told them my sad story . The engine would start with a choke full on but if you gave it gas it would chug painfully and end with the motor dying.Both mechanics said it was carb jets plugged. After three trips and $300 in repair costs... They just kept doing the same fix-- replace carb jets -- clean carb jets--results always ended in 90-ish good miles followed by more despair.I decided I would sell it for parts before I would spend one more minute or dollar for a 16 year old bike that looked good but ran like crap... But the engineer in me wouldn't give up (my poor wife). I looked at fuel samples under a microscope and did find some tiny black rubbery particles (straight from the tank) I bought a cheap USB led lighted endoscope (http://a.co/4Poleek ) I wanted one of these cameras anyway..and inspected the best I could-- but found nothing particularly bad...So I emptied the fuel and rinsed the tank well with water one more time. Cleaned the carb jets (I was getting faster at jet cleaning) and it ran great for about a day then more of the same. Stumped I decided to replace the $25 fuel pump and bought a high throughput fuel filter plus spark plugs. I have been sputter free ever since. Pump is likely a diaphragm type .. Could the handfuls of rust BTR (before tank refinishing) have degraded the pump? Could it have been a failed fuel pump coincidence ? Not sure but safe to say if you plan to refinish the tank -maybe consider replacing the fuel pump as well if you have exposed it to Gobs of rust particles -- if I had it to do over I'm sure I would have replaced the $25 pumpThe tank refinish was a success!! (masked by other problems) this cycle is running great just in time for Florida summer (when it feels like the surface of the sun) probably plan to sell it next chance I get to recoup my money but I learned a lot and met some nice people on instructables finally got the chance to "give back" best of luck to you all !